Arabis hastatula Greene, Leafl. Bot. Observ. Crit. 2: 79. 1910

Perennials; short- to long-lived; apomictic or sexual; caudex often woody. Stems 1-4 per caudex branch, arising from margin of rosette near ground surface, 1-3 dm, glabrous throughout. Basal leaves: blade linear-oblanceolate to oblanceolate, 1-3(-5) mm wide, margins entire or minutely toothed, rarely ciliate near petiole base, trichomes (simple), to 0.8 mm, surfaces pubescent or glabrous, trichomes short-stalked, 3-6-rayed, 0.07-0.2 mm. Cauline leaves: 4-15, not concealing stem; blade auricles 0.5-2.5 mm, surfaces of distalmost leaves glabrous. Racemes 12-40-flowered, usually unbranched. Fruiting pedicels reflexed, abruptly recurved near base, 4-8 mm, glabrous. Flowers divaricate to pendent at anthesis; sepals pubescent; petals lavender, 5-6 × ca. 1 mm, glabrous; pollen ellipsoid or spheroid. Fruits reflexed to closely pendent, usually appressed to rachis, often secund, straight, edges parallel, 0.3-0.42 cm × 1-1.5 mm; valves glabrous; ovules 46-60 per ovary. Seeds uniseriate, 1-1.3 × 0.8-1 mm; wing continuous, 0.05-0.1 mm wide.

Flowering Jun-Jul. Igneous rock outcrops; of conservation concern; 1900-2100 m; Oreg.

Both sexual and apomictic collections of Boechera hastatula have been identified; further study is needed to determine whether they truly are conspecific. The species is known only from Baker and Wallowa counties.